Rendimiento y dinámica de crecimiento estacional de ballico perenne, pastoreado con ovinos a diferentes frecuencias e intensidades

The objective of the present study was to assess perennial ryegrass seasonal herbage accumulation, growth rate (GR), tiller population density (TPD) and weight (TW) at different grazing frequencies and intensities. Treatments consisted of two grazing frequencies (14 and 21 d in the rainy season and 35 and 42 d in the dry and cold seasons) and three grazing intensities: (hard 4-6 cm), medium (6-8 cm) and lax (8-10 cm) in a completely randomized block design with a factorial 2x3 arrangement and three replicates. In the rainy season herbage accumulation was 28 % greater (Pballico perenne a diferentes frecuencias e intensidades de pastoreo. Los tratamientos consistieron en dos frecuencias 14 ó 21 días (época de lluvias) y 35 ó 42 días (épocas fría y seca) y tres intensidades de pastoreo: alta (IA: 4 - 6 cm), media (IM: 6 - 8 cm) y ligera (IL: 8 - 10 cm), se utilizó un diseño de bloques completos al azar con arreglo factorial 2 x 3 y tres repeticiones. En lluvias el pastorear cada 21 dás superó en 28 % al de 14 días (4,437 vs 3,457 kg MS ha-1) y durante las épocas fría y seca se produjo 27 % más forraje al pastorear cada 35 que a 42 días (2,270 vs 1,787 kg MS ha-1). La IM produjo mayor acumulación de forraje que la IA e IL, durante las tres épocas del año. La TC fue mayor en la época de lluvias, especialmente en agosto, cuando se pastoreó a IM cada 21 días. En las épocas fría y seca la mayor TC se registró con pastoreos cada 35 días a IM. En agosto se observó la mayor DT promedio (8,042 m-2) y disminuyó a partir de septiembre. El PT determinó la mayor acumulación de forraje a los 21 días en la época de lluvias, en tanto que la DT incrementó el rendimiento de forraje al inicio del siguiente periodo de lluvias

Structure and Optical Properties of Doped SiO2 Mesoporous Glasses

Monolithic mesoporous silica glasses were synthesized. The presence of Cu2+ and Fe3+ cations during the synthesis of sol-gel precursors leads to different morphologies and pore sizes. The materials are characterized via IR and Raman scattering spectra to detect surface groups and -Si-O-Si- rings (i.e., 3–6 Si atoms) and morphology is examined through electron microscopy. N2 sorption isotherms reveal details of the mesoporous structure of the materials, which are endowed with significantly large surface areas and pore volumes. Vapor percolation occurs in these samples because of a void arrangement consisting of pore bulges delimited by narrower necks. The optical characterization shows the luminescence spectrum and thermoluminescent behavior subjected to successive exposures of beta particles

Predictors of hyperlipidemia during the first half of pregnancy in Mexican women

Objective: To determine the predictors of hypercholesterolemia and of hypertriglyceridemia during the first half of pregnancy in Mexican women. Methods: Cross-sectional comparative study of pregnant women with less than 21 weeks of gestational age. Measurements: Demographic information, obstetric history, prepregnancy body mass index, cholesterol and triglycerides. Cross tabulations and multiple logistic regression were used for statistical analysis. Results: 230 participants; 61 women with normal prepregnancy body mass index, 108 with overweight, and 61 with obesity. Dyslipidemia was defined as elevated cholesterol (>180 mg/dL) or triglycerides (>170 mg/dL). After adjusting by potential confounders, independent predictors of hypercholesterolemia included being overweight (OR=2.8, 95% CI 1.4-5.9), being obese (OR=3.7 95% CI 1.6-8.4) or being on the second trimester of pregnancy. The same predictors were found for hypertriglyceridemia, respectively OR=2.8, 95% CI 1.4-5.6, OR=2.9, 95% CI 1.3-6.5, OR=2.6, 95% CI 1.4-4.7. Conclusion: Mexican women with prepregnancy overweight or obesity have greater risk of suffering hypercholesterolemia and hypertriglyceridemia during pregnancy. Women in the second trimester had higher levels of both lipids as compared to the first one. This is the first Mexican study that confirms the increase of lipids as gestational age progresses

Epizootiología de la tricoestrongilosis gastrointestinal en ovinos sometidos a tratamientos antiparasitarios selectivos en Cuba

Durante dos años se evaluó la epizootiología de la tricostrongilosis gastrointestinal en un rebaño de 72 ovejas Pelibuey, con edad promedio de cuatro años, sometidas a un esquema de tratamientos selectivos sobre la base de un estudio epizootiológico previo y el empleo de la carta FAMACHA©. Las ovejas se desparasitaron en tres momentos: al parto, a la mitad del periodo poco lluvioso y al destete; el resto del año se aplicó la estrategia de tratamientos selectivos mediante la coloración de la mucosa ocular. Se determinó el conteo fecal de huevos (CFH), la coloración de la mucosa ocular, el hematocrito y la condición corporal, a través de muestreos; así como el efecto de la época del año y del estado reproductivo en la carga parasitaria, mediante un análisis de varianza. Hubo un predominio de Haemonchus spp., con tendencia estacional en el CFH, que fue mayor durante el periodo poco lluvioso. El 59,1 % de los animales mostraron infestación baja (menos de 300 hpg) y solo el 6,6 % presentó infestación alta (más de 4 000 hpg), lo cual propició una tasa de 3,55 tratamientos por reproductora al año. Los valores de hematocrito promedio estuvieron por encima de 25 % en las dos épocas. Adicionalmente, el 98,8 % de los animales presentaron coloración de la mucosa ocular entre A y C de la carta de colores FAMACHA©, y las reproductoras vacía

Influence of gender on carcass yield of twin lambs Blackbelly x Pelibuey at 56 days of age

ABSTRACT The aim of this study was to determine the influence of gender on pre-weaning growth, yield and weight of primal cuts of the carcass of Blackbelly x Pelibuey lambs. 16 twin lambs were used. The lamb gender was the fixed factor. The variables evaluated were: body weight at birth and at weaning, average daily weight gain, weight and yield of carcass and primal cuts: neck, arm, thorax, abdomen and leg. Gender did not affect (P>0.05) body weight at birth. However, the pre-weaning average daily weight gain and body weight at weaning were affected (P0.05) by the gender of the lamb. Nevertheless, the area of the Longissimus dorsi muscle and cavity fat were different between males and females (P<0.05) 11.5±0.73cm2 and 198±0.05 g vs 9.3±0.73cm2 and 282±0.05g, respectively. In conclusion, in twin lambs Blackbelly x Pelibuey males had greater average daily weight gain and body weight at weaning than females. Carcass yield and weight and primal cuts were not affected by the gender of the lamb. However, males had greater area of the L. dorsi muscle than females and these in turn had a greater amount of cavity fat than males